Chatter While Turning

[GreggR]

Just finished my first pen. I adjusted the tailstock/headstock alignment, assured the mandrel was straight, at least as straight as threads will let it be... ran out 0.012 inches so I need to buy/make a new mandrel.

The blank closest to the headstock turned fine, no noise. The one closer the tailstock chattered quite a bit. I bought this "starter" kit that had pre-drilled blanks, and the one on the lathe was chosen because the hole wandered (I didn't plan on it being an assembled pen! Figured I wouldn't be so lucky), so after glue up one end of the barrel within the blank had a crescent of air between it and the barrel. It wasn't running real true even after I got it cleaned up. The gouge was sharp, as was the skew, like I said... everything worked fine on the blank nearest the headstock.

Having a machining background, when I hear chatter I know a) I am deflecting, b) the tool is dull or too low/high relative to centerline, c)the speed is too high, or d) the cut is too shallow. I played with all of these... but to no avail. It didn't affect the finished product except the turning was out of round relative to the barrel. The blank nearest the headstock was not, but then it had a snug and straight hole.

Did I just experience a badly drilled blank, or what did I do wrong??

 

[mrcook4570]

If tools were sharp, it could be that the tailstock and/or nut was overtightened, causing a bow in the mandrel. Or some wobble will be introduced by using the live center that came with the lathe - replace it with a 60 degree cone for metal working so it will fit the recess in the mandrel.

I also rotate the blanks on the bushings as approach final dimensions and in between sanding grits.

 

[JimQ]

Or it could be either a loose tailstock, or a sharp pointed live center. The mandrells are designed to make use of 60degree live centers. I found that when I switched to one, I eliminated most of my pen turning problems similar to yours.

JimQ

 

[Pipes]

The guys at woodcraft here told me to round the tip of the live center a touch that I use for the mandrel !! Duno if that is right or a help but the were very eemphatic about this !!! [8D]

 

[TomServo]

greg: I get some chatter too, but lack the knowledge of wood lathery to figure out the why and howfor..

 

[Gordon]

Greg

I have the same problem at times.

Try loosening or tightening the Tailstock Lock Handle - slightly.

Wish I knew more about this - looking forward to the comments/answers from others.

Good luck

Gordon

 

[Rifleman1776]

Just send your wife out of the shop. That's what I do. All chatter stops.

 

[Deere41h]

If you are using a Jet mini lathe, the live center you get with the lathe is not a 60 degree live center. It doesn't fit the end of the mandrel the way a true 60 degree center would. Try to find a 60 degree live center and try it. It should help solve your chatter problems.

 

[GreggR]

Thank you everyone. Some very good advice here, I will try all things mentioned. Frankly I am surprised I didn't blow out the blank.

"Send your wife out of the shop, all chatter stops"! [] I have a sign that says "anti-static area" with "X"'s through both a lightning bolt and a female symbol. My wife got it for me!

Now I just need to find a sign that works for my brother-in-law......

 

[jdavis]

Agree with the Rifleman. Send my chatterbox away. Really try loosening the tailstock a little. Also very shary tool. Hone it regulary.